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1 : : /* SPDX-License-Identifier: GPL-2.0 */
2 : : #ifndef __LINUX_BITMAP_H
3 : : #define __LINUX_BITMAP_H
4 : :
5 : : #ifndef __ASSEMBLY__
6 : :
7 : : #include <linux/types.h>
8 : : #include <linux/bitops.h>
9 : : #include <linux/string.h>
10 : : #include <linux/kernel.h>
11 : :
12 : : /*
13 : : * bitmaps provide bit arrays that consume one or more unsigned
14 : : * longs. The bitmap interface and available operations are listed
15 : : * here, in bitmap.h
16 : : *
17 : : * Function implementations generic to all architectures are in
18 : : * lib/bitmap.c. Functions implementations that are architecture
19 : : * specific are in various include/asm-<arch>/bitops.h headers
20 : : * and other arch/<arch> specific files.
21 : : *
22 : : * See lib/bitmap.c for more details.
23 : : */
24 : :
25 : : /**
26 : : * DOC: bitmap overview
27 : : *
28 : : * The available bitmap operations and their rough meaning in the
29 : : * case that the bitmap is a single unsigned long are thus:
30 : : *
31 : : * The generated code is more efficient when nbits is known at
32 : : * compile-time and at most BITS_PER_LONG.
33 : : *
34 : : * ::
35 : : *
36 : : * bitmap_zero(dst, nbits) *dst = 0UL
37 : : * bitmap_fill(dst, nbits) *dst = ~0UL
38 : : * bitmap_copy(dst, src, nbits) *dst = *src
39 : : * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
40 : : * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
41 : : * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
42 : : * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
43 : : * bitmap_complement(dst, src, nbits) *dst = ~(*src)
44 : : * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
45 : : * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
46 : : * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
47 : : * bitmap_empty(src, nbits) Are all bits zero in *src?
48 : : * bitmap_full(src, nbits) Are all bits set in *src?
49 : : * bitmap_weight(src, nbits) Hamming Weight: number set bits
50 : : * bitmap_set(dst, pos, nbits) Set specified bit area
51 : : * bitmap_clear(dst, pos, nbits) Clear specified bit area
52 : : * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area
53 : : * bitmap_find_next_zero_area_off(buf, len, pos, n, mask) as above
54 : : * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
55 : : * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
56 : : * bitmap_cut(dst, src, first, n, nbits) Cut n bits from first, copy rest
57 : : * bitmap_replace(dst, old, new, mask, nbits) *dst = (*old & ~(*mask)) | (*new & *mask)
58 : : * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
59 : : * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
60 : : * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
61 : : * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
62 : : * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
63 : : * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
64 : : * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
65 : : * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
66 : : * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
67 : : * bitmap_release_region(bitmap, pos, order) Free specified bit region
68 : : * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
69 : : * bitmap_from_arr32(dst, buf, nbits) Copy nbits from u32[] buf to dst
70 : : * bitmap_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst
71 : : * bitmap_get_value8(map, start) Get 8bit value from map at start
72 : : * bitmap_set_value8(map, value, start) Set 8bit value to map at start
73 : : *
74 : : * Note, bitmap_zero() and bitmap_fill() operate over the region of
75 : : * unsigned longs, that is, bits behind bitmap till the unsigned long
76 : : * boundary will be zeroed or filled as well. Consider to use
77 : : * bitmap_clear() or bitmap_set() to make explicit zeroing or filling
78 : : * respectively.
79 : : */
80 : :
81 : : /**
82 : : * DOC: bitmap bitops
83 : : *
84 : : * Also the following operations in asm/bitops.h apply to bitmaps.::
85 : : *
86 : : * set_bit(bit, addr) *addr |= bit
87 : : * clear_bit(bit, addr) *addr &= ~bit
88 : : * change_bit(bit, addr) *addr ^= bit
89 : : * test_bit(bit, addr) Is bit set in *addr?
90 : : * test_and_set_bit(bit, addr) Set bit and return old value
91 : : * test_and_clear_bit(bit, addr) Clear bit and return old value
92 : : * test_and_change_bit(bit, addr) Change bit and return old value
93 : : * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
94 : : * find_first_bit(addr, nbits) Position first set bit in *addr
95 : : * find_next_zero_bit(addr, nbits, bit)
96 : : * Position next zero bit in *addr >= bit
97 : : * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
98 : : * find_next_and_bit(addr1, addr2, nbits, bit)
99 : : * Same as find_next_bit, but in
100 : : * (*addr1 & *addr2)
101 : : *
102 : : */
103 : :
104 : : /**
105 : : * DOC: declare bitmap
106 : : * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
107 : : * to declare an array named 'name' of just enough unsigned longs to
108 : : * contain all bit positions from 0 to 'bits' - 1.
109 : : */
110 : :
111 : : /*
112 : : * Allocation and deallocation of bitmap.
113 : : * Provided in lib/bitmap.c to avoid circular dependency.
114 : : */
115 : : extern unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags);
116 : : extern unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags);
117 : : extern void bitmap_free(const unsigned long *bitmap);
118 : :
119 : : /*
120 : : * lib/bitmap.c provides these functions:
121 : : */
122 : :
123 : : extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
124 : : extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
125 : : extern int __bitmap_equal(const unsigned long *bitmap1,
126 : : const unsigned long *bitmap2, unsigned int nbits);
127 : : extern bool __pure __bitmap_or_equal(const unsigned long *src1,
128 : : const unsigned long *src2,
129 : : const unsigned long *src3,
130 : : unsigned int nbits);
131 : : extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
132 : : unsigned int nbits);
133 : : extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
134 : : unsigned int shift, unsigned int nbits);
135 : : extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
136 : : unsigned int shift, unsigned int nbits);
137 : : extern void bitmap_cut(unsigned long *dst, const unsigned long *src,
138 : : unsigned int first, unsigned int cut,
139 : : unsigned int nbits);
140 : : extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
141 : : const unsigned long *bitmap2, unsigned int nbits);
142 : : extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
143 : : const unsigned long *bitmap2, unsigned int nbits);
144 : : extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
145 : : const unsigned long *bitmap2, unsigned int nbits);
146 : : extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
147 : : const unsigned long *bitmap2, unsigned int nbits);
148 : : extern void __bitmap_replace(unsigned long *dst,
149 : : const unsigned long *old, const unsigned long *new,
150 : : const unsigned long *mask, unsigned int nbits);
151 : : extern int __bitmap_intersects(const unsigned long *bitmap1,
152 : : const unsigned long *bitmap2, unsigned int nbits);
153 : : extern int __bitmap_subset(const unsigned long *bitmap1,
154 : : const unsigned long *bitmap2, unsigned int nbits);
155 : : extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
156 : : extern void __bitmap_set(unsigned long *map, unsigned int start, int len);
157 : : extern void __bitmap_clear(unsigned long *map, unsigned int start, int len);
158 : :
159 : : extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
160 : : unsigned long size,
161 : : unsigned long start,
162 : : unsigned int nr,
163 : : unsigned long align_mask,
164 : : unsigned long align_offset);
165 : :
166 : : /**
167 : : * bitmap_find_next_zero_area - find a contiguous aligned zero area
168 : : * @map: The address to base the search on
169 : : * @size: The bitmap size in bits
170 : : * @start: The bitnumber to start searching at
171 : : * @nr: The number of zeroed bits we're looking for
172 : : * @align_mask: Alignment mask for zero area
173 : : *
174 : : * The @align_mask should be one less than a power of 2; the effect is that
175 : : * the bit offset of all zero areas this function finds is multiples of that
176 : : * power of 2. A @align_mask of 0 means no alignment is required.
177 : : */
178 : : static inline unsigned long
179 : 27 : bitmap_find_next_zero_area(unsigned long *map,
180 : : unsigned long size,
181 : : unsigned long start,
182 : : unsigned int nr,
183 : : unsigned long align_mask)
184 : : {
185 : 27 : return bitmap_find_next_zero_area_off(map, size, start, nr,
186 : : align_mask, 0);
187 : : }
188 : :
189 : : extern int bitmap_parse(const char *buf, unsigned int buflen,
190 : : unsigned long *dst, int nbits);
191 : : extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
192 : : unsigned long *dst, int nbits);
193 : : extern int bitmap_parselist(const char *buf, unsigned long *maskp,
194 : : int nmaskbits);
195 : : extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
196 : : unsigned long *dst, int nbits);
197 : : extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
198 : : const unsigned long *old, const unsigned long *new, unsigned int nbits);
199 : : extern int bitmap_bitremap(int oldbit,
200 : : const unsigned long *old, const unsigned long *new, int bits);
201 : : extern void bitmap_onto(unsigned long *dst, const unsigned long *orig,
202 : : const unsigned long *relmap, unsigned int bits);
203 : : extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
204 : : unsigned int sz, unsigned int nbits);
205 : : extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
206 : : extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
207 : : extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
208 : :
209 : : #ifdef __BIG_ENDIAN
210 : : extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
211 : : #else
212 : : #define bitmap_copy_le bitmap_copy
213 : : #endif
214 : : extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
215 : : extern int bitmap_print_to_pagebuf(bool list, char *buf,
216 : : const unsigned long *maskp, int nmaskbits);
217 : :
218 : : #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
219 : : #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
220 : :
221 : : /*
222 : : * The static inlines below do not handle constant nbits==0 correctly,
223 : : * so make such users (should any ever turn up) call the out-of-line
224 : : * versions.
225 : : */
226 : : #define small_const_nbits(nbits) \
227 : : (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG && (nbits) > 0)
228 : :
229 : 2254 : static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
230 : : {
231 : 2254 : unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
232 [ + - + - : 2251 : memset(dst, 0, len);
- - ]
233 : 0 : }
234 : :
235 : 11290 : static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
236 : : {
237 : 11290 : unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
238 [ + + ]: 11287 : memset(dst, 0xff, len);
239 : : }
240 : :
241 : 740 : static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
242 : : unsigned int nbits)
243 : : {
244 : 740 : unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
245 [ - - - + : 522 : memcpy(dst, src, len);
- - ]
246 : 0 : }
247 : :
248 : : /*
249 : : * Copy bitmap and clear tail bits in last word.
250 : : */
251 : : static inline void bitmap_copy_clear_tail(unsigned long *dst,
252 : : const unsigned long *src, unsigned int nbits)
253 : : {
254 : : bitmap_copy(dst, src, nbits);
255 : : if (nbits % BITS_PER_LONG)
256 : : dst[nbits / BITS_PER_LONG] &= BITMAP_LAST_WORD_MASK(nbits);
257 : : }
258 : :
259 : : /*
260 : : * On 32-bit systems bitmaps are represented as u32 arrays internally, and
261 : : * therefore conversion is not needed when copying data from/to arrays of u32.
262 : : */
263 : : #if BITS_PER_LONG == 64
264 : : extern void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf,
265 : : unsigned int nbits);
266 : : extern void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap,
267 : : unsigned int nbits);
268 : : #else
269 : : #define bitmap_from_arr32(bitmap, buf, nbits) \
270 : : bitmap_copy_clear_tail((unsigned long *) (bitmap), \
271 : : (const unsigned long *) (buf), (nbits))
272 : : #define bitmap_to_arr32(buf, bitmap, nbits) \
273 : : bitmap_copy_clear_tail((unsigned long *) (buf), \
274 : : (const unsigned long *) (bitmap), (nbits))
275 : : #endif
276 : :
277 : 225 : static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
278 : : const unsigned long *src2, unsigned int nbits)
279 : : {
280 [ + - + - ]: 225 : if (small_const_nbits(nbits))
281 [ - + - + : 225 : return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
- - - - ]
282 : 0 : return __bitmap_and(dst, src1, src2, nbits);
283 : : }
284 : :
285 : 63 : static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
286 : : const unsigned long *src2, unsigned int nbits)
287 : : {
288 [ - + - - ]: 63 : if (small_const_nbits(nbits))
289 [ + + - - ]: 9 : *dst = *src1 | *src2;
290 : : else
291 : 54 : __bitmap_or(dst, src1, src2, nbits);
292 : 54 : }
293 : :
294 : : static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
295 : : const unsigned long *src2, unsigned int nbits)
296 : : {
297 : : if (small_const_nbits(nbits))
298 : : *dst = *src1 ^ *src2;
299 : : else
300 : : __bitmap_xor(dst, src1, src2, nbits);
301 : : }
302 : :
303 : 0 : static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1,
304 : : const unsigned long *src2, unsigned int nbits)
305 : : {
306 [ # # # # ]: 0 : if (small_const_nbits(nbits))
307 [ # # # # ]: 0 : return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
308 : 0 : return __bitmap_andnot(dst, src1, src2, nbits);
309 : : }
310 : :
311 : 0 : static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
312 : : unsigned int nbits)
313 : : {
314 : 0 : if (small_const_nbits(nbits))
315 : : *dst = ~(*src);
316 : : else
317 : 0 : __bitmap_complement(dst, src, nbits);
318 : : }
319 : :
320 : : #ifdef __LITTLE_ENDIAN
321 : : #define BITMAP_MEM_ALIGNMENT 8
322 : : #else
323 : : #define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long))
324 : : #endif
325 : : #define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1)
326 : :
327 : 322 : static inline int bitmap_equal(const unsigned long *src1,
328 : : const unsigned long *src2, unsigned int nbits)
329 : : {
330 [ + - + - ]: 322 : if (small_const_nbits(nbits))
331 : 322 : return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
332 [ # # # # ]: 0 : if (__builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
333 : : IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
334 : 0 : return !memcmp(src1, src2, nbits / 8);
335 : 0 : return __bitmap_equal(src1, src2, nbits);
336 : : }
337 : :
338 : : /**
339 : : * bitmap_or_equal - Check whether the or of two bitmaps is equal to a third
340 : : * @src1: Pointer to bitmap 1
341 : : * @src2: Pointer to bitmap 2 will be or'ed with bitmap 1
342 : : * @src3: Pointer to bitmap 3. Compare to the result of *@src1 | *@src2
343 : : * @nbits: number of bits in each of these bitmaps
344 : : *
345 : : * Returns: True if (*@src1 | *@src2) == *@src3, false otherwise
346 : : */
347 : 0 : static inline bool bitmap_or_equal(const unsigned long *src1,
348 : : const unsigned long *src2,
349 : : const unsigned long *src3,
350 : : unsigned int nbits)
351 : : {
352 : 0 : if (!small_const_nbits(nbits))
353 : : return __bitmap_or_equal(src1, src2, src3, nbits);
354 : :
355 [ # # ]: 0 : return !(((*src1 | *src2) ^ *src3) & BITMAP_LAST_WORD_MASK(nbits));
356 : : }
357 : :
358 : 45 : static inline int bitmap_intersects(const unsigned long *src1,
359 : : const unsigned long *src2, unsigned int nbits)
360 : : {
361 [ # # # # ]: 45 : if (small_const_nbits(nbits))
362 [ - - + - : 36 : return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
- + # # #
# # # ]
363 : : else
364 : 0 : return __bitmap_intersects(src1, src2, nbits);
365 : : }
366 : :
367 : 387 : static inline int bitmap_subset(const unsigned long *src1,
368 : : const unsigned long *src2, unsigned int nbits)
369 : : {
370 [ # # # # ]: 387 : if (small_const_nbits(nbits))
371 [ + + + - : 168 : return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
+ - + - +
- + - + -
- + ]
372 : : else
373 : 99 : return __bitmap_subset(src1, src2, nbits);
374 : : }
375 : :
376 : 186 : static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
377 : : {
378 [ + - + - ]: 186 : if (small_const_nbits(nbits))
379 [ + + + + : 162 : return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
- + - - -
- - - - -
- - + - -
+ # # # #
# # # # #
# # # # #
# # # # #
# # # #
# ]
380 : :
381 : 24 : return find_first_bit(src, nbits) == nbits;
382 : : }
383 : :
384 : 1248 : static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
385 : : {
386 : 1248 : if (small_const_nbits(nbits))
387 : : return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
388 : :
389 : 1248 : return find_first_zero_bit(src, nbits) == nbits;
390 : : }
391 : :
392 : 284 : static __always_inline int bitmap_weight(const unsigned long *src, unsigned int nbits)
393 : : {
394 [ + - + - : 227 : if (small_const_nbits(nbits))
# # # # ]
395 [ - + - + ]: 302 : return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
396 : 0 : return __bitmap_weight(src, nbits);
397 : : }
398 : :
399 : 3087 : static __always_inline void bitmap_set(unsigned long *map, unsigned int start,
400 : : unsigned int nbits)
401 : : {
402 [ - + - - : 3087 : if (__builtin_constant_p(nbits) && nbits == 1)
+ + + - -
+ - - - +
- - ]
403 : 27 : __set_bit(start, map);
404 [ - + - - : 3054 : else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
- + - - -
+ - - ]
405 : 6 : IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
406 [ - - - - : 6 : __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
- + - - -
- - - - -
- - ]
407 : : IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
408 : 3 : memset((char *)map + start / 8, 0xff, nbits / 8);
409 : : else
410 : 3057 : __bitmap_set(map, start, nbits);
411 : 0 : }
412 : :
413 : 3252 : static __always_inline void bitmap_clear(unsigned long *map, unsigned int start,
414 : : unsigned int nbits)
415 : : {
416 [ - - - - : 3252 : if (__builtin_constant_p(nbits) && nbits == 1)
- + - - -
+ - - ]
417 : 3 : __clear_bit(start, map);
418 [ - - - - : 3249 : else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
- + - - -
+ - - ]
419 : 0 : IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
420 [ # # # # : 0 : __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
# # # # #
# # # ]
421 : : IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
422 : 0 : memset((char *)map + start / 8, 0, nbits / 8);
423 : : else
424 : 3249 : __bitmap_clear(map, start, nbits);
425 : : }
426 : :
427 : : static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src,
428 : : unsigned int shift, unsigned int nbits)
429 : : {
430 : : if (small_const_nbits(nbits))
431 : : *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift;
432 : : else
433 : : __bitmap_shift_right(dst, src, shift, nbits);
434 : : }
435 : :
436 : 0 : static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src,
437 : : unsigned int shift, unsigned int nbits)
438 : : {
439 [ # # # # ]: 0 : if (small_const_nbits(nbits))
440 : 0 : *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits);
441 : : else
442 : 0 : __bitmap_shift_left(dst, src, shift, nbits);
443 : 0 : }
444 : :
445 : : static inline void bitmap_replace(unsigned long *dst,
446 : : const unsigned long *old,
447 : : const unsigned long *new,
448 : : const unsigned long *mask,
449 : : unsigned int nbits)
450 : : {
451 : : if (small_const_nbits(nbits))
452 : : *dst = (*old & ~(*mask)) | (*new & *mask);
453 : : else
454 : : __bitmap_replace(dst, old, new, mask, nbits);
455 : : }
456 : :
457 : 7887 : static inline void bitmap_next_clear_region(unsigned long *bitmap,
458 : : unsigned int *rs, unsigned int *re,
459 : : unsigned int end)
460 : : {
461 : 7887 : *rs = find_next_zero_bit(bitmap, end, *rs);
462 : 7887 : *re = find_next_bit(bitmap, end, *rs + 1);
463 : 7887 : }
464 : :
465 : 0 : static inline void bitmap_next_set_region(unsigned long *bitmap,
466 : : unsigned int *rs, unsigned int *re,
467 : : unsigned int end)
468 : : {
469 : 0 : *rs = find_next_bit(bitmap, end, *rs);
470 : 0 : *re = find_next_zero_bit(bitmap, end, *rs + 1);
471 : 0 : }
472 : :
473 : : /*
474 : : * Bitmap region iterators. Iterates over the bitmap between [@start, @end).
475 : : * @rs and @re should be integer variables and will be set to start and end
476 : : * index of the current clear or set region.
477 : : */
478 : : #define bitmap_for_each_clear_region(bitmap, rs, re, start, end) \
479 : : for ((rs) = (start), \
480 : : bitmap_next_clear_region((bitmap), &(rs), &(re), (end)); \
481 : : (rs) < (re); \
482 : : (rs) = (re) + 1, \
483 : : bitmap_next_clear_region((bitmap), &(rs), &(re), (end)))
484 : :
485 : : #define bitmap_for_each_set_region(bitmap, rs, re, start, end) \
486 : : for ((rs) = (start), \
487 : : bitmap_next_set_region((bitmap), &(rs), &(re), (end)); \
488 : : (rs) < (re); \
489 : : (rs) = (re) + 1, \
490 : : bitmap_next_set_region((bitmap), &(rs), &(re), (end)))
491 : :
492 : : /**
493 : : * BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap.
494 : : * @n: u64 value
495 : : *
496 : : * Linux bitmaps are internally arrays of unsigned longs, i.e. 32-bit
497 : : * integers in 32-bit environment, and 64-bit integers in 64-bit one.
498 : : *
499 : : * There are four combinations of endianness and length of the word in linux
500 : : * ABIs: LE64, BE64, LE32 and BE32.
501 : : *
502 : : * On 64-bit kernels 64-bit LE and BE numbers are naturally ordered in
503 : : * bitmaps and therefore don't require any special handling.
504 : : *
505 : : * On 32-bit kernels 32-bit LE ABI orders lo word of 64-bit number in memory
506 : : * prior to hi, and 32-bit BE orders hi word prior to lo. The bitmap on the
507 : : * other hand is represented as an array of 32-bit words and the position of
508 : : * bit N may therefore be calculated as: word #(N/32) and bit #(N%32) in that
509 : : * word. For example, bit #42 is located at 10th position of 2nd word.
510 : : * It matches 32-bit LE ABI, and we can simply let the compiler store 64-bit
511 : : * values in memory as it usually does. But for BE we need to swap hi and lo
512 : : * words manually.
513 : : *
514 : : * With all that, the macro BITMAP_FROM_U64() does explicit reordering of hi and
515 : : * lo parts of u64. For LE32 it does nothing, and for BE environment it swaps
516 : : * hi and lo words, as is expected by bitmap.
517 : : */
518 : : #if __BITS_PER_LONG == 64
519 : : #define BITMAP_FROM_U64(n) (n)
520 : : #else
521 : : #define BITMAP_FROM_U64(n) ((unsigned long) ((u64)(n) & ULONG_MAX)), \
522 : : ((unsigned long) ((u64)(n) >> 32))
523 : : #endif
524 : :
525 : : /**
526 : : * bitmap_from_u64 - Check and swap words within u64.
527 : : * @mask: source bitmap
528 : : * @dst: destination bitmap
529 : : *
530 : : * In 32-bit Big Endian kernel, when using ``(u32 *)(&val)[*]``
531 : : * to read u64 mask, we will get the wrong word.
532 : : * That is ``(u32 *)(&val)[0]`` gets the upper 32 bits,
533 : : * but we expect the lower 32-bits of u64.
534 : : */
535 : 0 : static inline void bitmap_from_u64(unsigned long *dst, u64 mask)
536 : : {
537 : 0 : dst[0] = mask & ULONG_MAX;
538 : :
539 : 0 : if (sizeof(mask) > sizeof(unsigned long))
540 : : dst[1] = mask >> 32;
541 : : }
542 : :
543 : : /**
544 : : * bitmap_get_value8 - get an 8-bit value within a memory region
545 : : * @map: address to the bitmap memory region
546 : : * @start: bit offset of the 8-bit value; must be a multiple of 8
547 : : *
548 : : * Returns the 8-bit value located at the @start bit offset within the @src
549 : : * memory region.
550 : : */
551 : 0 : static inline unsigned long bitmap_get_value8(const unsigned long *map,
552 : : unsigned long start)
553 : : {
554 : 0 : const size_t index = BIT_WORD(start);
555 : 0 : const unsigned long offset = start % BITS_PER_LONG;
556 : :
557 : 0 : return (map[index] >> offset) & 0xFF;
558 : : }
559 : :
560 : : /**
561 : : * bitmap_set_value8 - set an 8-bit value within a memory region
562 : : * @map: address to the bitmap memory region
563 : : * @value: the 8-bit value; values wider than 8 bits may clobber bitmap
564 : : * @start: bit offset of the 8-bit value; must be a multiple of 8
565 : : */
566 : : static inline void bitmap_set_value8(unsigned long *map, unsigned long value,
567 : : unsigned long start)
568 : : {
569 : : const size_t index = BIT_WORD(start);
570 : : const unsigned long offset = start % BITS_PER_LONG;
571 : :
572 : : map[index] &= ~(0xFFUL << offset);
573 : : map[index] |= value << offset;
574 : : }
575 : :
576 : : #endif /* __ASSEMBLY__ */
577 : :
578 : : #endif /* __LINUX_BITMAP_H */
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